the tetrachord
sound object, live-electronic

The tetrachord features four sound sources. Four basic microphones are attached to a transparent plastic sheet stretched into a rectangle. This plastic sheet is suspended by springs, allowing it to vibrate. At the center of the object, a small engine with four arms interacts with the microphones by rubbing against the foil. The signals from the four piezo pickups are amplified and transmitted to four loudspeakers. These speakers are positioned in the same configuration in the room as the pickups on the object.